U.S. patent application number 11/961513 was filed with the patent office on 2009-06-25 for propeller assembly incorporating spindle with fins and overmolded bushing.
Invention is credited to Liheng Chen.
Application Number | 20090163089 11/961513 |
Document ID | / |
Family ID | 40789201 |
Filed Date | 2009-06-25 |
United States Patent
Application |
20090163089 |
Kind Code |
A1 |
Chen; Liheng |
June 25, 2009 |
Propeller Assembly Incorporating Spindle With Fins And Overmolded
Bushing
Abstract
A propeller assembly is provided for mounting on a rotatable
propeller shaft of a watercraft. The propeller assembly includes a
housing structure extending along a longitudinal axis. The housing
structure includes an outer surface and an inner surface defining a
cavity having a polygonal-shaped cross-section defined by at least
one corner and at least one sidewall. A bushing assembly is
receivable in the cavity of the housing structure. The bushing
assembly includes a spindle having an inner surface defining a
passageway for receiving the propeller shaft therethrough and an
outer surface having a plurality of circumferentially spaced fin
pairs extending therealong. Each fin pair includes a first fin
extending from the outer surface of the spindle and a second fin
extending from the outer surface of the spindle at a predetermined
angle to the first fin. The bushing assembly also includes a
bushing positioned between the spindle and the inner surface of the
housing structure.
Inventors: |
Chen; Liheng; (Elk Grove
Village, IL) |
Correspondence
Address: |
BOYLE FREDRICKSON S.C.
840 North Plankinton Avenue
MILWAUKEE
WI
53203
US
|
Family ID: |
40789201 |
Appl. No.: |
11/961513 |
Filed: |
December 20, 2007 |
Current U.S.
Class: |
440/49 ;
16/2.1 |
Current CPC
Class: |
B63H 2023/342 20130101;
F16C 2326/30 20130101; Y10T 16/05 20150115; F16C 3/02 20130101;
B63H 23/34 20130101 |
Class at
Publication: |
440/49 ;
16/2.1 |
International
Class: |
B63H 1/14 20060101
B63H001/14; F16C 9/00 20060101 F16C009/00 |
Claims
1. In a propeller assembly having a housing structure connectable
to a rotatable propeller shaft of a watercraft, the housing
structure extending along a longitudinal axis and having an inner
surface defining passageway therethrough, the improvement
comprising: a spindle receivable in the passageway of the housing,
the spindle having an inner surface defining a passageway for
receiving the propeller shaft therethrough and an outer surface;
and a plurality of circumferentially spaced, longitudinally
extending fin pairs, each fin pair including; a first fin extending
from the outer surface of the spindle and lying in a first plane;
and a second fin extending from the outer surface of the spindle
and lying in a second plane, the second plane being generally
parallel to and spaced from the first plane.
2. The improvement of claim 1 further comprising a bushing molded
over the outer surface of the spindle, the bushing including an
outer surface engageable with an inner surface of the housing
structure.
3. The improvement of claim 2 wherein the bushing is formed from a
resilient material.
4. The improvement of claim 3 wherein the bushing has a generally
square-shaped cross section and rounded corners.
5. The improvement of claim 1 wherein the inner surface of the
spindle includes a plurality of longitudinally extending
splines.
6. The improvement of claim 1 wherein the inner surface of the
housing structure has a generally square-shaped cross section and
wherein at least four fin pairs extend from the outer surface of
the spindle.
7. (canceled)
8. The improvement of claim 22 wherein the first fin of a second
fin pair is directed toward the first sidewall of the inner surface
of the housing structure and the second fin of the second fin pair
is directed toward the fourth sidewall.
9. The improvement of claim 1 wherein the fin pairs fragment from
the outer surface of the spindle in response to a predetermined
force thereon.
10. (canceled)
11. A propeller assembly for mounting on a rotatable propeller
shaft of a watercraft, comprising: a housing structure extending
along a longitudinal axis, the housing structure including an outer
surface and an inner surface defining a cavity having a
polygonal-shaped cross-section defined by at least one corner and
at least one sidewall; and a bushing assembly receiveable in the
cavity of the housing structure, the bushing assembly including: a
spindle having an inner surface defining a passageway for receiving
the propeller shaft therethrough and an outer surface having a
plurality of circumferentially spaced fin pairs extending
therealong, each fin pair including: a first fin extending from the
outer surface of the spindle and lying in a first plane; and a
second fin extending from the outer surface of the spindle and
lying in a second plane, the second plane being generally parallel
to and spaced from the first plane; and a bushing positioned
between the spindle and the inner surface of the housing
structure.
12. The propeller assembly of claim 11 wherein the bushing is
formed from a resilient material.
13. (canceled)
14. (canceled)
15. (canceled)
16. The propeller assembly of claim 23 wherein the first fin of a
second fin pair is directed toward the first sidewall of the inner
surface of the housing structure and the second fin of the second
fin pair is directed toward the fourth sidewall.
17. The propeller assembly of claim 11 wherein the fin pairs
fragment from the outer surface of the spindle in response to a
predetermined force thereon.
18. (canceled)
19. A propeller assembly for mounting on a rotatable propeller
shaft of a watercraft, comprising: a housing structure extending
along a longitudinal axis, the housing structure including an outer
surface and an inner surface defining a cavity, the inner surface
defined by: first and second spaced sidewalls, the first and second
sidewalls being generally parallel to each other; third and fourth
spaced sidewalls, the third and fourth sidewalls being generally
parallel to each other and being generally perpendicular to the
first and second spaced sidewalls; a bushing assembly including: a
spindle having an inner surface defining a passageway for receiving
the propeller shaft therethrough and an outer surface; a first fin
pair extending from the outer surface of the spindle and having a
first fin is directed towards the first sidewall of the inner
surface of the housing structure and a second fin directed towards
the third sidewall; a second fin pair extending from the outer
surface of the spindle and having a first fin is directed towards
the first sidewall of the inner surface of the housing structure
and a second fin directed towards the fourth sidewall; a third fin
pair extending from the outer surface of the spindle and having a
first fin is directed towards the second sidewall of the inner
surface of the housing structure and a second fin directed towards
the third sidewall; and a fourth fin pair extending from the outer
surface of the spindle and having a first fin is directed towards
the second sidewall of the inner surface of the housing structure
and a second fin directed towards the fourth sidewall.
20. The propeller assembly of claim 19 further comprising a bushing
positioned between the spindle and the inner surface of the housing
structure.
21. The propeller assembly of claim 20 wherein the bushing is
formed from a resilient material.
22. In a propeller assembly having a housing structure connectable
to a rotatable propeller shaft of a watercraft, the housing
structure extending along a longitudinal axis and having an inner
surface defining passageway therethrough, the improvement
comprising: a spindle receivable in the passageway of the housing,
the spindle having an inner surface defining a passageway for
receiving the propeller shaft therethrough and an outer surface;
and a plurality of circumferentially spaced, longitudinally
extending fin pairs, each fin pair including a first fin extending
from the outer surface of the spindle and a second fin extending
from the outer surface of the spindle at a predetermined angle to
the first fin. wherein: the inner surface of the housing structure
is defined by: first and second spaced sidewalls, the first and
second sidewalls being generally parallel to each other; and third
and fourth spaced sidewalls, the third and fourth sidewalls being
generally parallel to each other and being generally perpendicular
to the first and second spaced sidewalls; and the first fin of a
first fin pair is directed toward the first sidewall of the inner
surface of the housing structure and the second fin of the first
fin pair is directed toward the third sidewall.
23. A propeller assembly for mounting on a rotatable propeller
shaft of a watercraft, comprising: a housing structure extending
along a longitudinal axis, the housing structure including an outer
surface and an inner surface defining a cavity having a
polygonal-shaped cross-section defined by at least one corner and
at least one sidewall; and a bushing assembly receiveable in the
cavity of the housing structure, the bushing assembly including: a
spindle having an inner surface defining a passageway for receiving
the propeller shaft therethrough and an outer surface having a
plurality of circumferentially spaced fin pairs extending
therealong, each fin pair including a first fin extending from the
outer surface of the spindle and a second fin extending from the
outer surface of the spindle at a predetermined angle to the first
fin; and a bushing positioned between the spindle and the inner
surface of the housing structure; wherein: the inner surface of the
housing structure has a generally square-shaped cross section; the
at least one sidewall of the inner surface of the housing structure
includes: first and second spaced sidewalls, the first and second
sidewalls being generally parallel to each other; and third and
fourth spaced sidewalls, the third and fourth sidewalls being
generally parallel to each other and being generally perpendicular
to the first and second spaced sidewalls; and the first fin of a
first fin pair is directed toward the first sidewall of the inner
surface of the housing structure and the second fin of the first
fin pair is directed toward the third sidewall.
Description
FIELD OF THE INVENTION
[0001] This invention relates generally to propellers, and in
particular, to a propeller assembly for translating rotational
movement from a propeller shaft of a marine vehicle to the blades
of a propeller.
BACKGROUND AND SUMMARY OF THE INVENTION
[0002] It is known to propel a marine vehicle utilizing a propeller
assembly mounted on a rotatable drive shaft. The propeller assembly
includes a plurality of propeller blades extending radially from a
central hub. A motor rotates the drive shaft that, in turn, rotates
the propeller blades propelling the marine vehicle through the
water. Typically, the propeller assembly is constructed as a unit
wherein the propeller blades and the central hub are mounted or
removed from the drive shaft in unison. Alternatively, in order to
reduce the time and costs associated with replacing the propeller
blades, it has been contemplated to provide a propeller assembly
for a marine engine wherein the propeller blades project from a
propeller housing that is removable from a central hub.
[0003] By way of example, Chen, U.S. Pat. No. 5,967,751 discloses a
marine propeller assembly that includes a central hub secured to
the propeller shaft and having three or more axially extending keys
on the outer surface thereof. A propeller housing includes an inner
surface having three or more pairs of lobes for forming keyways
that receive the keys of the central hub. A retainer disc is
threaded on a propeller shaft and includes a plurality of angularly
spaced ears for engaging with the lobes on the inner surface on the
propeller housing in order to prevent the propeller housing from
being disengaged from the central hub.
[0004] While the advantages of a removal propeller housing are
readily apparent, it can be appreciated that it is often highly
desirable to retain the propeller assembly on the propeller shaft
in such a manner as to prevent any unnecessary movement of the
propeller assembly that may reduce the overall efficiency of the
drive system of the marine vehicle. However, during such
circumstances when the propeller blades engage a fixed object in
the water such as a rock or the like, it may become necessary for
the drive shaft of the marine vehicle to become disengaged from the
propeller housing in order to prevent damage to the drive system of
the marine vehicle. Consequently, it is desirable to provide a
propeller assembly that disengages from the drive shaft in response
to a predetermined force thereon. However, once a propeller
assembly has disengaged from the drive shaft, the operator
typically must replace the central hub or a component of the hub
before the propeller assembly can be used again. Further, it has
been noted that most damage to a drive system occurs within
5.degree. of rotation by the propeller shaft after the propeller
assembly stops rotating. For these reasons, it is highly desirable
to provide a propeller assembly that permits continued rotation of
the propeller shaft for at least 5.degree. after the propeller
housing disengages from the shaft.
[0005] In addition, it is known that the drive shafts driven by the
various motors for marine vehicles differ depending upon the
manufacture. Consequently, individual propellers must be provided
for the drive shafts of each motor brand. Maintaining an inventory
of specific propellers for each brand of motor requires significant
storage space and may be cost prohibitive.
[0006] Therefore, it is a primary object and feature of the present
invention to provide a propeller assembly which permits limited
continued rotation of the spindle and propeller shaft before
disengaging the propeller shaft from the propeller assembly.
[0007] It is still a further object and feature of the present
invention to provide a propeller assembly that may be simply and
easily mounted on and removed from the drive shaft of a marine
vehicle.
[0008] It is a still further object and feature of the present
invention to provide a propeller assembly that may be easily
adapted for mounting on the drive shafts of different
manufacturers' motors.
[0009] It is a still further object and feature of the present
invention to provide a propeller assembly that is simple and
inexpensive to manufacture.
[0010] In accordance with the present invention, an improvement in
a propeller assembly having a housing structure connectable to a
rotatable propeller shaft of a watercraft is provided. The housing
structure extends along a longitudinal axis and has an inner
surface defining passageway therethrough. The improvement includes
a spindle receivable in the passageway of the housing. The spindle
has an inner surface defining a passageway for receiving the
propeller shaft therethrough and an outer surface. The improvement
also includes plurality of circumferentially spaced, longitudinally
extending fin pairs. Each fin pair includes a first fin extending
from the outer surface of the spindle and a second fin extending
from the outer surface of the spindle at a predetermined angle to
the first fin.
[0011] A bushing is molded over the outer surface of the spindle.
The bushing includes an outer surface engageable with an inner
surface of the housing structure. The bushing is formed from a
resilient material and has a generally square-shaped cross section
and rounded corners. The inner surface of the spindle includes a
plurality of longitudinally extending splines.
[0012] The inner surface of the housing structure has a generally
square-shaped cross section and at least four fin pairs extend from
the outer surface of the spindle. The inner surface of the housing
structure is defined by first, second, third and fourth sidewalls.
The first and second sidewalls is generally parallel to each other.
The third and fourth sidewalls are generally parallel to each other
and generally perpendicular to the first and second spaced
sidewalls. The first fin of a first fin pair is directed toward the
first sidewall of the inner surface of the housing structure and
the second fin of the first fin pair is directed toward the third
sidewall. The first fin of a second fin pair is directed toward the
first sidewall of the inner surface of the housing structure and
the second fin of the second fin pair is directed toward the fourth
sidewall. It is contemplated for the fin pairs to fragment from the
outer surface of the spindle in response to a predetermined force
thereon.
[0013] In accordance with a further aspect of the present
invention, a propeller assembly is provided for mounting on a
rotatable propeller shaft of a watercraft. The propeller assembly
includes a housing structure extending along a longitudinal axis.
The housing structure includes an outer surface and an inner
surface defining a cavity having a polygonal-shaped cross-section
defined by at least one corner and at least one sidewall. A bushing
assembly is receivable in the cavity of the housing structure. The
bushing assembly includes a spindle having an inner surface
defining a passageway for receiving the propeller shaft
therethrough and an outer surface having a plurality of
circumferentially spaced fin pairs extending therealong. Each fin
pair includes a first fin extending from the outer surface of the
spindle and a second fin extending from the outer surface of the
spindle at a predetermined angle to the first fin. A bushing is
positioned between the spindle and the inner surface of the housing
structure.
[0014] The bushing is formed from a resilient material and the
inner surface of the housing structure has a generally
square-shaped cross section. The at least one sidewall of the inner
surface of the housing structure includes first and second spaced
sidewalls being generally parallel to each other and third and
fourth sidewalls being generally parallel to each other and
perpendicular to the first and second spaced sidewalls. The first
fin of a first fin pair is directed toward the first sidewall of
the inner surface of the housing structure and the second fin of
the first fin pair is directed toward the third sidewall. The first
fin of a second fin pair is directed toward the first sidewall of
the inner surface of the housing structure and the second fin of
the second fin pair is directed toward the fourth sidewall. It is
contemplated for the fin pairs to fragment from the outer surface
of the spindle in response to a predetermined force thereon.
[0015] In accordance with a still further aspect of the present
invention, a propeller assembly is provided for mounting on a
rotatable propeller shaft of a watercraft. The propeller assembly
includes a housing structure extending along a longitudinal axis.
The housing structure includes an outer surface and an inner
surface defining a cavity. The inner surface is defined by first,
second, third and fourth sidewalls. The first and second sidewalls
are generally parallel to each other. The third and fourth
sidewalls are generally parallel to each other and perpendicular to
the first and second spaced sidewalls. A bushing assembly includes
a spindle having an inner surface defining a passageway for
receiving the propeller shaft therethrough and an outer surface. A
first fin pair extends from the outer surface of the spindle and
has a first fin is directed towards the first sidewall of the inner
surface of the housing structure and a second fin directed towards
the third sidewall. A second fin pair extends from the outer
surface of the spindle and has a first fin is directed towards the
first sidewall of the inner surface of the housing structure and a
second fin directed towards the fourth sidewall. A third fin pair
extends from the outer surface of the spindle and has a first fin
is directed towards the second sidewall of the inner surface of the
housing structure and a second fin directed towards the third
sidewall. A fourth fin pair extends from the outer surface of the
spindle and has a first fin is directed towards the second sidewall
of the inner surface of the housing structure and a second fin
directed towards the fourth sidewall.
[0016] A bushing is positioned between the spindle and the inner
surface of the housing structure. The bushing is formed from a
resilient material.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The drawings furnished herewith illustrate a preferred
construction of the present invention in which the above advantages
and features are clearly disclosed as well as others which will be
readily understood from the following description of the
illustrated embodiment.
[0018] In the drawings:
[0019] FIG. 1 is an exploded, isometric view of a propeller
assembly of an embodiment of the present invention;
[0020] FIG. 2 is an enlarged view of the propeller assembly of FIG.
1;
[0021] FIG. 3 is a cross-sectional view of the propeller assembly
of the present invention taken along line 3-3 of FIG. 2;
[0022] FIG. 4 is a cross-sectional view of the propeller assembly
of the present invention taken along line 4-4 of FIG. 3 showing the
propeller assembly during normal operating conditions;
[0023] FIG. 5 is a cross-sectional view of the propeller assembly
of the present invention taken along line 4-4 of FIG. 3 showing the
propeller assembly at a first time period after the propeller
housing has stopped rotating while the propeller shaft continues to
rotate;
[0024] FIG. 6 is a cross-sectional view of the propeller assembly
of the present invention, similar to FIG. 5, showing the propeller
assembly at a second time period after the propeller housing has
stopped rotating while the propeller shaft continues to rotate;
[0025] FIG. 7 is a cross-sectional view of an alternate embodiment
of the propeller assembly of the present invention, similar to FIG.
3, showing the propeller assembly during normal operating
conditions;
[0026] FIG. 8 is a cross-sectional view of the propeller assembly
of the present invention, similar to FIG. 7, showing the propeller
assembly at a first time period after the propeller housing has
stopped rotating while the propeller shaft continues to rotate;
and
[0027] FIG. 9 is a cross-sectional view of the propeller assembly
of the present invention, similar to FIG. 8, showing the propeller
assembly at a second time period after the propeller housing has
stopped rotating while the propeller shaft continues to rotate.
DETAILED DESCRIPTION OF THE DRAWINGS
[0028] Referring to FIG. 1, a propeller assembly in accordance with
the present invention is generally designated by the reference
numeral 10. It is intended that propeller assembly 10 be mounted on
a rotatable propeller shaft 12 which, in turn, is driven by a
marine engine (not shown). Propeller shaft 12 extends along a
longitudinal axis and terminates at a threaded terminal end 14
adapted for receiving a locking nut 16 thereon, for reasons
hereinafter described. As is conventional, rotatable shaft 12
includes an outer surface 17 having longitudinally extending
splines 18 therealong adjacent terminal end 14.
[0029] Referring to FIGS. 1-3, propeller assembly 10 includes a
central hub 20 having a generally cylindrical inner housing 22 and
a generally cylindrical outer housing 24. Outer housing 24 has an
outer surface 26 and an inner surface 28. A plurality of
circumferentially spaced propeller blades 30 project radially from
outer surface 26 of outer housing 24. Inner surface 28 defines an
inner housing receipt cavity 32 for receiving inner housing 22
therein. Outer surface 34 of inner housing 22 and inner surface 28
of outer housing 24 are rigidly connected by a plurality of
circumferentially spaced connection spokes 38a-38c extend
therebetween. Spokes 38a-38c are circumferentially spaced about the
outer surface 34 of inner housing 22.
[0030] Inner housing 22 of central hub 20 includes an inner surface
36 defining inner cavity 37 for receiving bushing assembly 60, as
hereinafter described. Inner housing 22 further includes first and
second opposite ends 40 and 42, respectively. End flange 44
projects radially inward from second end 42 of inner housing 22 and
terminates at a radially inner surface 46 which defines generally
circular opening 48. As best seen in FIGS. 4-6, inner surface 36 of
inner housing 22 is partially defined by first, second, third and
fourth circumferentially spaced, longitudinally extending faces
39a-39d, respectively. First and third faces 39a and 39c,
respectively, are generally parallel to and face each other.
Similarly, second and fourth faces 39b and 39d, respectively, are
generally parallel to and face each other. In addition, first and
third faces 39a and 39c, respectively, are generally perpendicular
to second and fourth faces 39b and 39d, respectively. Faces 39a-39d
and outer surface 66 of spindle 62 are spaced by predetermined
distances D1. It can be appreciated that as described, cavity 37
within inner housing 22 has a generally square cross-section.
[0031] First side 41a of first face 39a is interconnect to second
side 43b of second face 39b by a generally arcuate, longitudinally
extending first corner 45a. First side 43a of second face 39b is
interconnect to second side 47b of third face 39c by a generally
arcuate, longitudinally extending second corner 45b. First side 47a
of third face 39c is interconnect to second side 49b of fourth face
39d by a generally arcuate, longitudinally extending third corner
45c. First side 49a of fourth face 39d is interconnect to second
side 41b of first face 39a by a generally arcuate, longitudinally
extending fourth corner 45d. For reasons hereinafter described,
with propeller assembly 10 assembled, it can be appreciated the
inner surfaces 51a-51d, of corners 45a-45d, respectively, are a
predetermined distance D2 from outer surface 66 of spindle 62.
[0032] Propeller assembly 10 further includes bushing assembly 60
which is intended to translate rotation of propeller shaft 12 to
central hub 20. Bushing assembly 60 includes spindle 62 having an
inner surface 64 and a generally cylindrical outer surface 66.
Inner surface 64 of spindle 62 includes a plurality of
longitudinally extending splines 70 extending therealong which are
intended to mesh with splines 18 extending along propeller shaft 12
when bushing assembly 60 is mounted thereon.
[0033] A plurality of circumferentially spaced, longitudinally
extending fin pairs 68a-68d project radially from outer surface 66
of spindle 62. Each fin pair 68a-68d includes a first fin 71 and a
second fin 73 generally perpendicular to first fin 71. First and
second fins 71 and 73 of each fin pair 68a-68d terminate at
corresponding end surfaces 71a and 73a, respectively. End surfaces
71a and 73a of first and second fins 71 and 73, respectively, of
fin pairs 68a-68d are radially spaced from outer surface 66 of
spindle 62 by a predetermined distance D3. For reasons hereafter
described, distance D3 is greater than distance D1 and less than
distance D2. It is contemplated for first and second fins 71 and
73, respectively, of fin pairs 68a-68d to be frangible such that
first and second fins 71 and 73, respectively, of fin pairs 68a-68d
disengage from outer surface 66 of spindle 62 in response to a
predetermined force thereon.
[0034] Bushing assembly 60 further includes bushing 72 fabricated
from any one of various resilient natural or synthetic materials
which normally retain their molded shape, permit some flexing and
distortion under shear, and resume their molded shape after the
stress is removed. Bushing 72 includes outer surface 74 corresponds
in shape to inner surface 36 of inner housing 22 of central hub 20.
More specifically, outer surface 74 of bushing 72 is partially
defined by is partially defined by first, second, third and fourth
circumferentially spaced, longitudinally extending faces 69a-69d,
respectively. First and third faces 69a and 69c, respectively, are
generally parallel to and face each other. Similarly, second and
fourth faces 69b and 69d, respectively, are generally parallel to
and face each other. In addition, first and third faces 69a and
69c, respectively, are generally perpendicular to second and fourth
faces 69b and 69d, respectively. Faces 69a-69d and longitudinal
axis 13 are spaced by predetermined distances D1.
[0035] First side 75a of first face 69a is interconnected to second
side 77b of second face 69b by a generally arcuate, longitudinally
extending first corner 79a. First side 77a of second face 69b is
interconnected to second side 81b of third face 69c by a generally
arcuate, longitudinally extending second corner 79b. First side 81a
of third face 69c is interconnected to second side 83b of fourth
face 69d by a generally arcuate, longitudinally extending third
corner 79c. First side 83a of fourth face 69d is interconnected to
second side 75b of first face 69a by a generally arcuate,
longitudinally extending fourth corner 79d. For reasons hereinafter
described, it can be appreciated the outer surfaces 85a-85d, of
corners 79a-79d, respectively, are a predetermined distance D2 from
outer surface 66 of spindle 62. As described, bushing assembly 60
has a generally square-shaped cross section.
[0036] As best seen in FIG. 4, bushing 72 is molded over the
spindle 62 such that second fin 73 of fin pair 68a and first fin 71
of fin pair 68b extend toward corresponding first face 69a of
bushing 72; second fin 73 of fin pair 68b and first fin 71 of fin
pair 68c extend toward corresponding second face 69b of bushing 72;
second fin 73 of fin pair 68c and first fin 71 of fin pair 68d
extend toward corresponding third face 69c of bushing 72; and
second fin 73 of fin pair 68d and first fin 71 of fin pair 68a
extend toward corresponding fourth face 69d bushing 72. As
described, it is contemplated for second fin 73 of fin pair 68a and
first fin 71 of fin pair 68b to be generally parallel; second fin
73 of fin pair 68b and first fin 71 of fin pair 68c to be generally
parallel; second fin 73 of fin pair 68c and first fin 71 of fin
pair 68d to be generally parallel; and second fin 73 of fin pair
68d and first fin 71 of fin pair 68a to be generally parallel.
[0037] In order to assemble a propeller assembly 10, bushing
assembly 60 is inserted within inner cavity 37 of inner housing 22
such that outer surface 74 of bushing 72 engages inner surface 36
of inner housing 22 and such that first end 76 of bushing assembly
60 is positioned against end flange 44. More specifically, faces
69a-69d of bushing 72 engage corresponding faces 39a-39d of inner
surface 36 of inner housing 22 and outer surfaces 85a-85d of
corners 79a-79d, respectively, of bushing 72 engage corresponding
inner surfaces 51a-51d of corners 45a-45d, respectively, of inner
housing 22 of central hub 20.
[0038] In order to mount the propeller assembly 10 on propeller
shaft 12, terminal end 14 of propeller shaft 12 is axially inserted
through bushing assembly 60 such that splines 18 on outer surface
17 of propeller shaft 12 mesh with splines 70 along inner surface
64 of spindle 62 and such that terminal end 14 of propeller shaft
12 extends through the opening 48 defined by flange 44 of inner
housing 22. Spider washer 90 is positioned on terminal end 14 of
propeller shaft 12 adjacent outer surface 44a of flange 44 of inner
housing. Spider washer 90 includes an inner surface 92 defining a
passageway 94 therethrough. Longitudinally extending splines 98
extend along a first portion 96 of inner surface 92 of spider
washer 90 and are adapted to mesh with splines 18 of propeller
shaft 12. Inner surface 92 of spider washer 90 further includes a
second portion 97 defined an enlarged portion 100 of passageway 94.
Enlarged portion 100 of passageway 94 has is sufficient dimension
to receive locking nut 16 threaded on terminal end 14 of propeller
shaft 12 therein. It is contemplated for a plurality of
circumferentially spaced tabs 102 to extend from outer surface 104
of spider washer 90. Tabs 102 are adapted for receiving a tab
washer (not shown) which may be provided by selected OEM
manufacturers of marine drive equipment in order to help maintain
propeller assembly 10 on drive shaft 12.
[0039] As is conventional, meshed splines 18 and 70 of propeller
shaft 12 and spindle 62, respectively, translate rotation of
propeller shaft 12 to central hub 20 through bushing assembly 60.
Rotation of the propeller blades 30 projecting from outer surface
26 of outer housing 24 propels a marine vehicle through the water.
If propeller blades 30 become fixed due to engagement with an
object in the water such that the propeller blades cannot rotate,
it can be appreciated that the engine of the marine vehicle will
continue to attempt to rotate propeller shaft 12. As a result,
rotational force will be exerted on first and second fins 71 and 73
of each fin pairs 68a-68d projecting from outer surface 66 of
spindle 62 by the propeller shaft 12. If the force on first and
second fins 71 and 73 exceeds a predetermined force, first and
second fins 71 and 73 of each fin pairs 68a-68d will compress
bushing 72 and rotate. As shown in FIG. 5, first and second fins 71
and 73 of each fin pairs 68a-68d only rotate a few degrees until
second fins 73 of fin pairs 68a-68d engage corresponding faces
39a-39d of inner surface 36 of inner housing 22 since end surfaces
73a of second fins 73 of fin pairs 68a-68d are a greater radial
distance D3 from outer surface 66 of spindle 62 than the distance
D1 that faces 39a-39d are from outer surface 66 of spindle 62.
[0040] During operation of a marine vehicle in a body of water,
rotation of propeller shaft 12 is translated to propeller assembly
10 such that propeller blades 30 propel the marine vehicle through
the body of water. In the event that propeller blades 30 become
fixed due to engagement with an object in the water, it can be
appreciated that the engine of the marine vehicle will continue to
attempt to rotate propeller shaft 12. With propeller assembly 10
fixed by the object in the body of water, the rotational force
generated by propeller shaft 12 on bushing assembly 60 will urge
first fins 71 of fin pairs 68a-68d towards corresponding second
sides 41b, 43b, 47b and 49b of corresponding faces 39a-39d of inner
surface 36 of inner housing 22, FIG. 5, as heretofore described.
With first fins 71 of fin pairs 68a-68d engaging corresponding
second sides 41b, 43b, 47b and 49b of corresponding faces 39a-39d
of inner surface 36 of inner housing 22, it is contemplated for
first fins 71 of fin pairs 68a-68d to fragment from outer surface
66 of spindle 62 in response to predetermined forces thereon.
[0041] In the event that propeller blades 30 become disengaged from
the object in the water after second fins 73 of fin pairs 68a-68d
fragment from outer surface 66 of spindle 62, FIG. 6, it can be
appreciated that first fins 71 of fin pairs 68a-68d have the
ability to translate the rotational force generated by propeller
shaft 12 to central hub 20 of propeller assembly 10, as heretofore
described. However, if propeller blades 30 of propeller assembly 10
remain fixed by the object in the body of water, the rotational
force generated by propeller shaft 12 on bushing assembly 60 will
urge first fins 71 of fin pairs 68a-68d into engagement with
corresponding faces 39a-39d of inner surface 36 of inner housing
22, as heretofore described. With first fins 71 of fin pairs
68a-68d engaging corresponding faces 39a-39d of inner surface 36 of
inner housing 22, it is contemplated for first fins 73 of fin pairs
68a-68d to fragment from outer surface 66 of spindle 62 in response
to predetermined forces thereon. In the event that first and second
fins 71 and 73 of fin pairs 68a-68d fragment from outer surface 66
of spindle 62, bushing assembly 60 is free to rotate within cavity
37 of inner housing 22. In such manner, it is intended to avoid
damage to the engine and to the drive system of the marine
vehicle.
[0042] It can be appreciated that propeller assembly 10 may be
assembled as heretofore described prior to the mounting thereof on
propeller shaft 12. In such manner, bushing assembly 60 may be
modified so as to adapt to various types of propeller shafts 12
produced by different manufacturers. In other words, utilizing a
modified bushing assembly 60, propeller assembly 10 may be mounted
on each of the various types of propeller shafts.
[0043] As best seen in FIG. 7, bushing 72 may be molded over the
spindle 62 such that second fin 73 of fin pair 68a and first fin 71
of fin pair 68b extend toward corresponding corner 79a of bushing
72; second fin 73 of fin pair 68b and first fin 71 of fin pair 68c
extend toward corresponding corner 79b of bushing 72; second fin 73
of fin pair 68c and first fin 71 of fin pair 68d extend toward
corresponding corner 79c of bushing 72; and second fin 73 of fin
pair 68d and first fin 71 of fin pair 68a extend toward
corresponding corner 79d of bushing 72. As described, it is
contemplated for second fin 73 of fin pair 68a and first fin 71 of
fin pair 68b to be generally parallel; second fin 73 of fin pair
68b and first fin 71 of fin pair 68c to be generally parallel;
second fin 73 of fin pair 68c and first fin 71 of fin pair 68d to
be generally parallel; and second fin 73 of fin pair 68d and first
fin 71 of fin pair 68a to be generally parallel.
[0044] In operation, rotation of the propeller blades 30 projecting
from outer surface 26 of outer housing 24 propels a marine vehicle
through the water. If propeller blades 30 become fixed due to
engagement with an object in the water such that the propeller
blades cannot rotate, it can be appreciated that the engine of the
marine vehicle will continue to attempt to rotate propeller shaft
12. As a result, rotational force will be exerted on first and
second fins 71 and 73 of each fin pairs 68a-68d projecting from
outer surface 66 of spindle 62 by the propeller shaft 12. If the
force on first and second fins 71 and 73 exceeds a predetermined
force, first and second fins 71 and 73 of each fin pairs 68a-68d
will compress bushing 72 and rotate.
[0045] With propeller assembly 10 fixed by the object in the body
of water, the rotational force generated by propeller shaft 12 on
bushing assembly 60 will urge first fins 71 of fin pairs 68a-68d
into engagement with corresponding second sides 41b, 43b, 47b and
49b of corresponding faces 39a-39d of inner surface 36 of inner
housing 22, FIG. 8. With first fins 71 of fin pairs 68a-68d
engaging corresponding second sides 41b, 43b, 47b and 49b of
corresponding faces 39a-39d of inner surface 36 of inner housing
22, it is contemplated for first fins 71 of fin pairs 68a-68d to
fragment from outer surface 66 of spindle 62 in response to
predetermined forces thereon, FIG. 9.
[0046] In the event that propeller blades 30 become disengaged from
the object in the water after first fins 71 of fin pairs 68a-68d
fragment from outer surface 66 of spindle 62, it can be appreciated
that second fins 73 of fin pairs 68a-68d have the ability to
translate the rotational force generated by propeller shaft 12 to
central hub 20 of propeller assembly 10, as heretofore described.
However, if propeller blades 30 of propeller assembly 10 remain
fixed by the object in the body of water, the rotational force
generated by propeller shaft 12 on bushing assembly 60 will urge
second fins 73 of fin pairs 68a-68d into engagement with
corresponding second sides 41b, 43b, 47b and 49b of corresponding
faces 39a-39d of inner surface 36 of inner housing 22, as
heretofore described. With second fins 73 of fin pairs 68a-68d
engaging corresponding second sides 41b, 43b, 47b and 49b of
corresponding faces 39a-39d of inner surface 36 of inner housing
22, it is contemplated for second fins 73 of fin pairs 68a-68d to
fragment from outer surface 66 of spindle 62 in response to
predetermined forces thereon. In the event that first and second
fins 71 and 73 of fin pairs 68a-68d fragment from outer surface 66
of spindle 62, bushing assembly 60 is free to rotate within cavity
37 of inner housing 22. In such manner, it is intended to avoid
damage to the engine and to the drive system of the marine
vehicle.
[0047] Further, various modes of carrying out the invention are
contemplated as being within the scope of the following claims
particularly pointing out and distinctly claiming the subject
matter which is regarded as the invention.
* * * * *